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<FONT color="green">001</FONT>    /*<a name="line.1"></a>
<FONT color="green">002</FONT>     * Copyright (C) 2008-2012, fluid Operations AG<a name="line.2"></a>
<FONT color="green">003</FONT>     *<a name="line.3"></a>
<FONT color="green">004</FONT>     * FedX is free software: you can redistribute it and/or modify<a name="line.4"></a>
<FONT color="green">005</FONT>     * it under the terms of the GNU Affero General Public License as<a name="line.5"></a>
<FONT color="green">006</FONT>     * published by the Free Software Foundation, either version 3 of the<a name="line.6"></a>
<FONT color="green">007</FONT>     * License, or (at your option) any later version.<a name="line.7"></a>
<FONT color="green">008</FONT>     * <a name="line.8"></a>
<FONT color="green">009</FONT>     * This program is distributed in the hope that it will be useful,<a name="line.9"></a>
<FONT color="green">010</FONT>     * but WITHOUT ANY WARRANTY; without even the implied warranty of<a name="line.10"></a>
<FONT color="green">011</FONT>     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the<a name="line.11"></a>
<FONT color="green">012</FONT>     * GNU Affero General Public License for more details.<a name="line.12"></a>
<FONT color="green">013</FONT>     * <a name="line.13"></a>
<FONT color="green">014</FONT>     * You should have received a copy of the GNU Affero General Public License<a name="line.14"></a>
<FONT color="green">015</FONT>     * along with this program.  If not, see &lt;http://www.gnu.org/licenses/&gt;.<a name="line.15"></a>
<FONT color="green">016</FONT>     */<a name="line.16"></a>
<FONT color="green">017</FONT>    <a name="line.17"></a>
<FONT color="green">018</FONT>    package com.fluidops.fedx.optimizer;<a name="line.18"></a>
<FONT color="green">019</FONT>    <a name="line.19"></a>
<FONT color="green">020</FONT>    import java.util.List;<a name="line.20"></a>
<FONT color="green">021</FONT>    import java.util.Set;<a name="line.21"></a>
<FONT color="green">022</FONT>    <a name="line.22"></a>
<FONT color="green">023</FONT>    import org.apache.log4j.Logger;<a name="line.23"></a>
<FONT color="green">024</FONT>    import org.openrdf.query.BindingSet;<a name="line.24"></a>
<FONT color="green">025</FONT>    import org.openrdf.query.Dataset;<a name="line.25"></a>
<FONT color="green">026</FONT>    import org.openrdf.query.algebra.QueryRoot;<a name="line.26"></a>
<FONT color="green">027</FONT>    import org.openrdf.query.algebra.TupleExpr;<a name="line.27"></a>
<FONT color="green">028</FONT>    import org.openrdf.query.algebra.evaluation.impl.ConstantOptimizer;<a name="line.28"></a>
<FONT color="green">029</FONT>    import org.openrdf.query.algebra.evaluation.impl.DisjunctiveConstraintOptimizer;<a name="line.29"></a>
<FONT color="green">030</FONT>    import org.openrdf.query.algebra.evaluation.impl.EvaluationStrategyImpl;<a name="line.30"></a>
<FONT color="green">031</FONT>    import org.openrdf.sail.SailException;<a name="line.31"></a>
<FONT color="green">032</FONT>    <a name="line.32"></a>
<FONT color="green">033</FONT>    import com.fluidops.fedx.FedX;<a name="line.33"></a>
<FONT color="green">034</FONT>    import com.fluidops.fedx.FederationManager;<a name="line.34"></a>
<FONT color="green">035</FONT>    import com.fluidops.fedx.algebra.SingleSourceQuery;<a name="line.35"></a>
<FONT color="green">036</FONT>    import com.fluidops.fedx.cache.Cache;<a name="line.36"></a>
<FONT color="green">037</FONT>    import com.fluidops.fedx.structures.Endpoint;<a name="line.37"></a>
<FONT color="green">038</FONT>    import com.fluidops.fedx.structures.QueryInfo;<a name="line.38"></a>
<FONT color="green">039</FONT>    <a name="line.39"></a>
<FONT color="green">040</FONT>    <a name="line.40"></a>
<FONT color="green">041</FONT>    <a name="line.41"></a>
<FONT color="green">042</FONT>    public class Optimizer {<a name="line.42"></a>
<FONT color="green">043</FONT>    <a name="line.43"></a>
<FONT color="green">044</FONT>            public static Logger logger = Logger.getLogger(Optimizer.class);<a name="line.44"></a>
<FONT color="green">045</FONT>            <a name="line.45"></a>
<FONT color="green">046</FONT>            <a name="line.46"></a>
<FONT color="green">047</FONT>            public static TupleExpr optimize(TupleExpr parsed, Dataset dataset, BindingSet bindings, <a name="line.47"></a>
<FONT color="green">048</FONT>                            EvaluationStrategyImpl strategy, QueryInfo queryInfo) throws SailException {<a name="line.48"></a>
<FONT color="green">049</FONT>                    <a name="line.49"></a>
<FONT color="green">050</FONT>                    FedX fed = FederationManager.getInstance().getFederation();<a name="line.50"></a>
<FONT color="green">051</FONT>                    List&lt;Endpoint&gt; members = fed.getMembers();<a name="line.51"></a>
<FONT color="green">052</FONT>                    <a name="line.52"></a>
<FONT color="green">053</FONT>                    // if the federation has a single member only, evaluate the entire query there<a name="line.53"></a>
<FONT color="green">054</FONT>                    if (members.size()==1 &amp;&amp; queryInfo.getQuery()!=null)<a name="line.54"></a>
<FONT color="green">055</FONT>                            return new SingleSourceQuery(parsed, members.get(0), queryInfo);                        <a name="line.55"></a>
<FONT color="green">056</FONT>                    <a name="line.56"></a>
<FONT color="green">057</FONT>                    // Clone the tuple expression to allow for more aggressive optimizations<a name="line.57"></a>
<FONT color="green">058</FONT>                    TupleExpr query = new QueryRoot(parsed.clone());<a name="line.58"></a>
<FONT color="green">059</FONT>                    <a name="line.59"></a>
<FONT color="green">060</FONT>                    Cache cache = FederationManager.getInstance().getCache();<a name="line.60"></a>
<FONT color="green">061</FONT>    <a name="line.61"></a>
<FONT color="green">062</FONT>                    if (logger.isTraceEnabled())<a name="line.62"></a>
<FONT color="green">063</FONT>                            logger.trace("Query before Optimization: " + query);<a name="line.63"></a>
<FONT color="green">064</FONT>                    <a name="line.64"></a>
<FONT color="green">065</FONT>                    <a name="line.65"></a>
<FONT color="green">066</FONT>                    /* original sesame optimizers */<a name="line.66"></a>
<FONT color="green">067</FONT>                    new ConstantOptimizer(strategy).optimize(query, dataset, bindings);             // maybe remove this optimizer later<a name="line.67"></a>
<FONT color="green">068</FONT>    <a name="line.68"></a>
<FONT color="green">069</FONT>                    new DisjunctiveConstraintOptimizer().optimize(query, dataset, bindings);<a name="line.69"></a>
<FONT color="green">070</FONT>    <a name="line.70"></a>
<FONT color="green">071</FONT>                    <a name="line.71"></a>
<FONT color="green">072</FONT>                    /*<a name="line.72"></a>
<FONT color="green">073</FONT>                     * TODO<a name="line.73"></a>
<FONT color="green">074</FONT>                     * add some generic optimizers: <a name="line.74"></a>
<FONT color="green">075</FONT>                     *  - FILTER ?s=1 &amp;&amp; ?s=2 =&gt; EmptyResult<a name="line.75"></a>
<FONT color="green">076</FONT>                     *  - Remove variables that are not occuring in query stmts from filters<a name="line.76"></a>
<FONT color="green">077</FONT>                     */<a name="line.77"></a>
<FONT color="green">078</FONT>                    <a name="line.78"></a>
<FONT color="green">079</FONT>                    <a name="line.79"></a>
<FONT color="green">080</FONT>                    /* custom optimizers, execute only when needed*/<a name="line.80"></a>
<FONT color="green">081</FONT>                            <a name="line.81"></a>
<FONT color="green">082</FONT>                    GenericInfoOptimizer info = new GenericInfoOptimizer(queryInfo);<a name="line.82"></a>
<FONT color="green">083</FONT>                    <a name="line.83"></a>
<FONT color="green">084</FONT>                    // collect information and perform generic optimizations<a name="line.84"></a>
<FONT color="green">085</FONT>                    info.optimize(query);<a name="line.85"></a>
<FONT color="green">086</FONT>                    <a name="line.86"></a>
<FONT color="green">087</FONT>                    // Source Selection: all nodes are annotated with their source<a name="line.87"></a>
<FONT color="green">088</FONT>                    SourceSelection sourceSelection = new SourceSelection(members, cache, queryInfo);<a name="line.88"></a>
<FONT color="green">089</FONT>                    sourceSelection.doSourceSelection(info.getStatements());<a name="line.89"></a>
<FONT color="green">090</FONT>                                    <a name="line.90"></a>
<FONT color="green">091</FONT>                    // if the query has a single relevant source (and if it is no a SERVICE query), evaluate at this source only<a name="line.91"></a>
<FONT color="green">092</FONT>                    Set&lt;Endpoint&gt; relevantSources = sourceSelection.getRelevantSources();<a name="line.92"></a>
<FONT color="green">093</FONT>                    if (relevantSources.size()==1 &amp;&amp; !info.hasService())<a name="line.93"></a>
<FONT color="green">094</FONT>                            return new SingleSourceQuery(query, relevantSources.iterator().next(), queryInfo);              <a name="line.94"></a>
<FONT color="green">095</FONT>                    <a name="line.95"></a>
<FONT color="green">096</FONT>                    if (info.hasService())<a name="line.96"></a>
<FONT color="green">097</FONT>                            new ServiceOptimizer(queryInfo).optimize(query);<a name="line.97"></a>
<FONT color="green">098</FONT>                    <a name="line.98"></a>
<FONT color="green">099</FONT>                    // optimize Filters, if available<a name="line.99"></a>
<FONT color="green">100</FONT>                    if (info.hasFilter())<a name="line.100"></a>
<FONT color="green">101</FONT>                            new FilterOptimizer().optimize(query);<a name="line.101"></a>
<FONT color="green">102</FONT>    <a name="line.102"></a>
<FONT color="green">103</FONT>                    // optimize unions, if available<a name="line.103"></a>
<FONT color="green">104</FONT>                    if (info.hasUnion)<a name="line.104"></a>
<FONT color="green">105</FONT>                            new UnionOptimizer(queryInfo).optimize(query);<a name="line.105"></a>
<FONT color="green">106</FONT>                    <a name="line.106"></a>
<FONT color="green">107</FONT>                    // optimize statement groups and join order<a name="line.107"></a>
<FONT color="green">108</FONT>                    new StatementGroupOptimizer(queryInfo).optimize(query);<a name="line.108"></a>
<FONT color="green">109</FONT>                                    <a name="line.109"></a>
<FONT color="green">110</FONT>                    new VariableScopeOptimizer(queryInfo).optimize(query);<a name="line.110"></a>
<FONT color="green">111</FONT>                    <a name="line.111"></a>
<FONT color="green">112</FONT>                    if (logger.isTraceEnabled())<a name="line.112"></a>
<FONT color="green">113</FONT>                            logger.trace("Query after Optimization: " + query);<a name="line.113"></a>
<FONT color="green">114</FONT>    <a name="line.114"></a>
<FONT color="green">115</FONT>                    return query;<a name="line.115"></a>
<FONT color="green">116</FONT>            }       <a name="line.116"></a>
<FONT color="green">117</FONT>    <a name="line.117"></a>
<FONT color="green">118</FONT>    }<a name="line.118"></a>




























































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